1. The ornamental design for a portable computer, as shown and described.

Description:

FIG. 1 is a front, top perspective view of a first embodiment showing our new design;

FIG. 2 is front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof;

FIG. 8 is a front, top perspective view of a second embodiment showing our new design;

FIG. 9 is front view thereof;

FIG. 10 is a rear view thereof;

FIG. 11 is a left side view thereof;

FIG. 12 is a right side view thereof;

FIG. 13 is a top view thereof;

FIG. 14 is a bottom view thereof;

FIG. 15 is a front, top perspective view of a third embodiment showing our new design;

FIG. 16 is front view thereof;

FIG. 17 is a rear view thereof;

FIG. 18 is a left side view thereof;

FIG. 19 is a right side view thereof;

FIG. 20 is a top view thereof; and,

FIG. 21 is a bottom view thereof.

The portion of the portable computer shown in gray shading represents a metallic- looking surface. The broken line showing is for the purpose of illustrating portions of the portable computer and forms no part of the claimed design.